This invention pertains to a system for automatically adjusting computer gray scale or color images in order to compensate for deviations resulting from the use of input devices such as scanners and/or output devices such as printers. In this manner, the print or video display of the image closely matches the original image, be it a computer rendered image or an image which was initially received via a scanner. The system accounts for the particular printing process used and for any programs that subsequently manipulate the image or prepare it for printing by doing color separation and half tone generation.